It is common to erect exterior lighting around domestic, industrial, or military property to provide security against intruders, and to provide lighting for visitors and authorized personnel. The need frequently arises for the lighting system to provide a “customized” light pattern, in which a beam of light is desired to be cast in one specific direction, but not in other directions.
In a domestic or residential application where it is common for homes to be built close to each other, the outdoor lighting of one home might project light into a neighbor's home. In the close quarters of some metropolitan areas, such spill over lighting is an irritant, especially if the light illuminates the interior of a neighbor's bedroom during sleeping hours.
To customize the light pattern for such outdoor lighting, one conventional solution is to place a moveable or rotatable shield within the light fixture to block the emitted light with the opaque shield. An example of such a rotating shield is disclosed in U.S. Pat. Nos. 6,095,665 and 6,322,234 (Drake, et al.). When it is desired to change or alter the direction of the blocked light, the user rotates the shield to the desired location. The size and shape of the shield blocking the light in the Drake design is set at the factory and cannot be adjusted in the field. Another rotating light shield in the automotive application is disclosed in, for example, U.S. Pat. No. 5,057,983 (Ulrich, Sr.).
However, a rotatable shield has several disadvantages. One disadvantage is that the shield may be inadvertently moved from its set position by forces such as wind or physical vibration of the supporting structure. Another disadvantage is that shield and attachment hardware are difficult to fabricate and not easily adjusted to precisely block light. Yet another disadvantage is that the shield has a prefabricated shape that is determined during manufacture. Such a predetermined shape does not permit exact tailoring in the field by the consumer to fit the myriad of lighting applications. Thus, such a rotatable shield does not enable the installer or homeowner to truly customize the light pattern by selective blocking the light emission.
Thus, there is a need for a lighting system that provides a light shield whose shape may be customized, during installation in the field, to precisely conform the emitted light to the user's wishes. Further, there is a need for a lighting system that provides a light shield that is of simple construction.